The primary goal of this project is to analyze the effects of managed care on a broad set of characteristics of physicians' practices, such as their incomes, their hours worked, patient loads, fees charged, the mix of patients seen, satisfaction from medical practice, and the degree of ethical discomfort with managed care arrangements. In order to conduct these analyses, we will take advantage of a unique longitudinal data set of physicians who were previously surveyed in 1991 (and in 1987 for about half of the sample). We propose to resurvey a subset of these physicians in 1996, which will also provide current descriptive information about the nature of the physicians' arrangements with managed care organizations. In order to meet these objectives, the proposed project will (1) refine and expand the survey instrument used in the 1991 Survey of Young Physicians, which was supported by the Robert Wood Johnson Foundation and (2) reinterview the subset of 1991 respondents who are located in the 75 largest metropolitan statistical areas, spend at least 20 hours per week in patient care, and have remained in the same practice between 1991 and 1996. It is estimated that about 1,500 interviews will be completed. This research design was selected in order to focus the survey resources on physicians in areas most likely to be affected by the changing health care market, especially the growth of HMOs, and to deal with the problem of physicians' selection into practices of particular characteristics. Although the sample we will analyze will also be a selected sample, namely, physicians who chose to stay in the same practice, this selection problem can be addressed with standard statistical methods. Analyses of this sample will produce good estimates of the effects of exogenous changes in the health care market on physicians.